The present invention relates to a blood circulating medical device, and more particularly to a device for preparing a blood platelet gel in a closed circuit system wherein the closed circuit system utilizes only the blood of the patient being operated on, for infusing blood and platelet gel into the patient.
In certain surgical procedures it is common for blood to be given to the patient during the procedure. In most cases, this blood is supplied through a transfusion wherein the blood being given to the patient is blood that is provided by a third party, or is supplied by the patient herself from blood the patient donated earlier to a blood bank for use in the surgery.
However, such blood transfusions are not suitable for all patients. For example, patients of certain religious groups (e.g. Jehovah""s Witness) cannot accept blood transfusions because it violates their religious beliefs. This prohibition usually extends not only to blood transfusions from third parties, but also blood transfusions that originated from the patient herself from earlier withdrawn blood. For example, it would be a violation of certain religious beliefs to withdraw a pint of blood (commonly known as a unit) from the patient prior to surgery, and then reintroduce the blood into the same patient at a later date.
In order to comply with these religious requirements, blood can be withdrawn from the patient, so long as the blood is placed into a closed loop, unbroken circuit, and then reintroduced into the patient from that circuit, without the circuit being broken.
Another issue in blood transfusion operations relates to the issue of stanching the flow of blood from the arteries and/or veins that are cut during surgery. During the middle ages and thereafter, it was common practice during a medical operation, such as a leg amputation, to cut off the flow from blood vessels by placing a hot poker against the open ends of the blood vessels to seal the blood vessels shut through melting the blood vessels together. This process was extremely painful, and was known commonly as cauterization. Although cauterization of the type practiced during the middle ages is no longer performed, some cauterization techniques are still used in certain circumstances.
An advancement over cauterization involves the use of physically closing the arteries with a non-heated object, such as by using a needle and thread to sew the artery or vein shut, thereby preventing blood from flowing out of the artery or vein. Another technique exists that involves the use of a xe2x80x9cgluexe2x80x9d that comprises a mixture of fiber and glue. The fiber and glue is used in some procedures to actually glue the ends of the arteries or veins shut, hereby stanching the flow of blood.
In recent years, an improved xe2x80x9cplatelet gelxe2x80x9d method has been invented for stanching the flow of blood. The original platelet gel technology was developed at the United States Naval Hospital in San Diego, Calif. by Dr. Paul S. Potter and Mr Andrew G. Hood. Dr. Potter and Mr. Hood discovered that the platelet gel, when applied to a wound, would stop tie flow of bleeding.
Platelet gel technology uses the clotting factors found in the blood""s platelets to cause clots within the arteries or veins, thereby stanching the flow of blood from the blood vessels. The platelet gel technique basically involves the manufacture of a platelet gel from platelets harvested from blood. The harvested platelets are mixed with various materials to form a gel, and the gel is applied to the wound. Platelet gel technology is currently used rather extensively in cardiovascular surgeries, orthopaedic surgeries, and in ear, nose and throat surgeries.
The harvesting of platelet cells from blood usually requires that whole blood be separated into fractions through centrifigation. During the centrifugation of blood, the blood separates into three fractions. In particular, the red cell fraction comprising mostly red blood cells migrates to the radially outer portion of the centrifuge tube or barrel, and the plasma fraction migrates to the radially inner portion of the centrifuge tube or barrel since the plasma fraction is half as dense as the red cell fraction. The centrifugation of blood causes a platelet rich fraction to form at a position radially outward of the plasma fraction, and radially inward of the red cell fraction. Basically, the platelet rich fraction between the red cell fraction and the plasma fraction includes platelets in a bed of white cells (i.e. leukocytes). As is well known, white blood cells help fight infection in a wound. More specifically, the platelet rich fraction includes white cells, a few red cells, a small amount of plasma, and a high quantity of platelets. The platelet rich fraction is commonly referred to as platelet rich plasma (PRP).
Each platelet has three growth hormones per platelet. For instance, a sample of blood having a 1,000,000 platelet count would also have a 3,000,000 growth hormone count. When the platelet gel is placed into the wound, the growth hormones of the platelets tend to accelerate the healing process within the wound. Also, the white cells are activated by being placed into the wound and begin to fight infection. Because the wound has been open, the white blood cells in the platelet gel become a defense mechanism within the wound.
The existence of these white cells within the platelet gel make the platelet gel superior to the xe2x80x9cartificial gluexe2x80x9d discussed above, since the artificial glue has neither the growth hormones nor white blood cells (i.e. leukocytes). As such the artificial glue does not accelerate the healing process and does not furnish the wound with a natural defense mechanism that defends the wound against infection.
While the above described platelet gel technology has many benefits to current surgical procedures, known platelet gel techniques suffer some deficiencies. In particular, no known technique has the capability of being used in a closed corporeal circuit. Further, prior known techniques do not lend themselves to use with a closed corporeal circuit.
As discussed above, a closed corporeal circuit is a circuit wherein blood is drawn from the body, such as by being suctioned out of an open wound, passed through a flow path within a network of tubing, centrifuged in a cell washer (e.g. a Fresenius CATS device), and then returned to the body without ever leaving the circuit. Normally, a circuit such as that described above is unnecessary. However, for those who refuse transfusions, the use of such a circuit is the only viable way that lost blood can be restored.
One problem with the refusal to accept a transfusion is that such a refusal increases the risk faced by the patient during surgery because of the inability to supply the patient with additional blood. Due to the increased risk and possibly enhanced malpractice liability, many surgeons and doctors refuse to perform surgery on such patients. Therefore, a refusal to accept transfusions also limits the availability of practitioners who are willing to perform surgery on the patient.
An additional way that the use of a platelet gel helps to reduce the risk of surgery is that the platelet gel helps the surgeon identify xe2x80x9cbleeders,xe2x80x9d which are blood vessels which have been cut or nicked, and are therefore leaking blood. When the platelet gel is placed into the wound, the bleeders actually pulsate against the platelet gel, thus providing an additional visual indication of the bleeder. If the identified bleeder is large, the surgeon may clear the platelet gel from the bleeder, cauterize the bleeder, and then re-apply the platelet gel before closing the patient. By identifying the bleeders in the above manner, the physician and the patient are spared the trauma of going back into surgery to stop a previously unidentified bleeder.
The present invention addresses the above-identified need, as well as others, with a platelet gel manufacturer for use with a closed corporeal system that is operable to intravenously extract blood from a patient and separate extracted blood to obtain platelet rich plasma. The platelet gel manufacturer includes a platelet gel applicator, a controllable platelet receptacle, a controllable coagulant receptacle, and a controllable platelet gel receptacle. The controllable platelet receptacle is fluidly coupled to the closed corporeal system, the controllable coagulant receptacle is fluidly coupled to the controllable platelet gel receptacle, and the controllable platelet gel receptacle is fluidly coupled to the platelet gel applicator. The controllable platelet receptacle is operable to receive the platelet rich plasma obtained from the patient by the closed corporeal system, and controllably deliver the platelet rich plasma to the controllable platelet gel receptacle. The controllable coagulant receptacle is operable to store a coagulant used to produce platelet gel, and controllably deliver the coagulant to the controllable platelet gel receptacle. The controllable platelet gel receptacle is operable to receive the platelet rich plasma from the controllable platelet receptacle, receive the coagulant from the controllable coagulant receptacle, and controllably deliver a platelet gel comprising the platelet rich plasma and the coagulant to the platelet gel applicator. Further, the platelet gel applicator is operable to receive platelet gel from the controllable platelet gel receptacle, and deliver the platelet gel to a selected location of the patient in order to promote healing at the selected location.
Pursuant to another embodiment of the present invention, there is provided a system suitable for manufacturing and delivering platelet gel in a closed corporeal circuit. The system includes a blood draw system, a blood pheresis system, and a platelet gel manufacturer. The blood draw system includes a blood reservoir operable to store blood, and an intravenous draw tube operable to draw blood from a vein of a patient and deliver the blood to the blood reservoir. The blood pheresis system includes a centrifuge fluidly coupled to the blood reservoir in order to receive the blood from the blood reservoir. The centrifuge extracts platelet rich plasma comprising platelets and white blood cells from the blood of the patient. The platelet gel manufacturer is fluidly coupled to the blood pheresis system in order to receive the platelet rich plasma. The platelet gel manufacturer is operable to combine the platelet rich plasma with a coagulant to obtain a platelet gel, and deliver the platelet gel to a selected location of the patient in order to promote healing at the selected location.
Pursuant to a further embodiment of the present invention, a platelet gel manufacturer for use with a closed corporeal system is operable to intravenously extract blood from a patient and separate extracted blood to obtain platelet rich plasma. The platelet gel manufacturer includes a platelet gel applicator, a first platelet syringe, a coagulant syringe, a first platelet gel syringe, and tubing. The tubing fluidly couples the platelet gel applicator, the first platelet syringe, the coagulant syringe, and the first platelet gel syringe. The first platelet syringe is operable to receive a first portion of the platelet rich plasma obtained from the patient by the closed corporeal system, and controllably deliver the first portion of the platelet rich plasma to the first platelet gel syringe via the tubing. The coagulant syringe stores a coagulant used to produce platelet gel, and delivers a first portion of the coagulant to the first platelet gel syringe via the tubing. The first platelet gel syringe receives the platelet rich plasma from the first platelet syringe via the tubing, receives the coagulant from the coagulant syringe via the tubing, and controllably delivers a first platelet gel comprising the first portion of the platelet rich plasma and the first portion of the coagulant to the platelet gel applicator via the tubing. The platelet gel applicator receives platelet gel from the first platelet gel syringe, and delivers the platelet gel to selected locations of the patient in order to promote healing at the selected locations.
It is an object of the present invention to provide an improved platelet gel manufacturer and system for manufacturing platelet gel.
It is also an object of the present invention to provide a new and useful platelet gel manufacturer and system for manufacturing platelet gel.
It is another object of the present invention to provide a system of manufacturing platelet gel in a closed corporeal circuit.
It is yet another object of the present invention to provide a platelet gel manufacturer suitable for manufacturing and delivering platelet gel to patients whose religious beliefs do not permit blood transfusions such Jehovah""s Witnesses.
The above and other objects, features, and advantages of the present invention will become apparent from the following description and the attached drawings.